NetBSD/sys/dev/i2c/max77620.c

288 lines
7.3 KiB
C

/* $NetBSD: max77620.c,v 1.6 2018/06/26 06:03:57 thorpej Exp $ */
/*-
* Copyright (c) 2017 Jared McNeill <jmcneill@invisible.ca>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: max77620.c,v 1.6 2018/06/26 06:03:57 thorpej Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/device.h>
#include <sys/conf.h>
#include <sys/bus.h>
#include <sys/kmem.h>
#include <sys/gpio.h>
#include <dev/i2c/i2cvar.h>
#include <dev/fdt/fdtvar.h>
#define MAX_GPIO_REG(n) (0x36 + (n))
#define MAX_GPIO_DEBOUNCE __BITS(7,6)
#define MAX_GPIO_INT __BITS(5,4)
#define MAX_GPIO_OUTPUT_VAL __BIT(3)
#define MAX_GPIO_INPUT_VAL __BIT(2)
#define MAX_GPIO_DIR __BIT(1)
#define MAX_GPIO_DRV __BIT(0)
#define MAX_GPIO_COUNT 8
struct max77620_softc {
device_t sc_dev;
i2c_tag_t sc_i2c;
i2c_addr_t sc_addr;
int sc_phandle;
};
struct max77620_pin {
struct max77620_softc *pin_sc;
int pin_num;
int pin_flags;
bool pin_actlo;
};
static const struct device_compatible_entry compat_data[] = {
{ "maxim,max77620", 0 },
{ NULL, 0 }
};
static uint8_t
max77620_read(struct max77620_softc *sc, uint8_t reg, int flags)
{
uint8_t val = 0;
int error;
error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP, sc->sc_addr,
&reg, 1, &val, 1, flags);
if (error != 0)
aprint_error_dev(sc->sc_dev, "error reading reg %#x: %d\n", reg, error);
return val;
}
static void
max77620_write(struct max77620_softc *sc, uint8_t reg, uint8_t val, int flags)
{
int error;
error = iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP, sc->sc_addr,
&reg, 1, &val, 1, flags);
if (error != 0)
aprint_error_dev(sc->sc_dev, "error writing reg %#x: %d\n", reg, error);
}
#define I2C_READ(sc, reg) max77620_read((sc), (reg), I2C_F_POLL)
#define I2C_WRITE(sc, reg, val) max77620_write((sc), (reg), (val), I2C_F_POLL)
#define I2C_LOCK(sc) iic_acquire_bus((sc)->sc_i2c, I2C_F_POLL)
#define I2C_UNLOCK(sc) iic_release_bus((sc)->sc_i2c, I2C_F_POLL)
static int
max77620_gpio_config(struct max77620_softc *sc, int pin, int flags)
{
uint32_t gpio;
KASSERT(pin >= 0 && pin < MAX_GPIO_COUNT);
gpio = I2C_READ(sc, MAX_GPIO_REG(pin));
switch (flags & (GPIO_PIN_INPUT|GPIO_PIN_OUTPUT)) {
case GPIO_PIN_INPUT:
gpio |= MAX_GPIO_DIR;
break;
case GPIO_PIN_OUTPUT:
gpio &= ~MAX_GPIO_DIR;
break;
default:
return EINVAL;
}
switch (flags & (GPIO_PIN_PUSHPULL|GPIO_PIN_OPENDRAIN)) {
case GPIO_PIN_PUSHPULL:
gpio |= MAX_GPIO_DRV;
break;
case GPIO_PIN_OPENDRAIN:
gpio &= ~MAX_GPIO_DRV;
break;
default:
return EINVAL;
}
I2C_WRITE(sc, MAX_GPIO_REG(pin), gpio);
return 0;
}
static void *
max77620_gpio_acquire(device_t dev, const void *data, size_t len, int flags)
{
struct max77620_softc * const sc = device_private(dev);
struct max77620_pin *gpin;
const u_int *gpio = data;
int error;
if (len != 12)
return NULL;
const uint8_t pin = be32toh(gpio[1]) & 0xff;
const bool actlo = (be32toh(gpio[2]) & __BIT(0)) != 0;
const bool pushpull = (be32toh(gpio[2]) & __BIT(1)) == 0;
const bool opendrain = (be32toh(gpio[2]) & __BIT(2)) != 0;
if (pushpull)
flags |= GPIO_PIN_PUSHPULL;
if (opendrain)
flags |= GPIO_PIN_OPENDRAIN;
if (pin >= MAX_GPIO_COUNT)
return NULL;
I2C_LOCK(sc);
error = max77620_gpio_config(sc, pin, flags);
I2C_UNLOCK(sc);
if (error != 0) {
device_printf(dev, "bad pin %d config %#x\n", pin, flags);
return NULL;
}
gpin = kmem_zalloc(sizeof(*gpin), KM_SLEEP);
gpin->pin_sc = sc;
gpin->pin_num = pin;
gpin->pin_flags = flags;
gpin->pin_actlo = actlo;
return gpin;
}
static void
max77620_gpio_release(device_t dev, void *priv)
{
struct max77620_softc * const sc = device_private(dev);
struct max77620_pin *gpin = priv;
I2C_LOCK(sc);
max77620_gpio_config(sc, gpin->pin_num, GPIO_PIN_INPUT|GPIO_PIN_OPENDRAIN);
I2C_UNLOCK(sc);
kmem_free(gpin, sizeof(*gpin));
}
static int
max77620_gpio_read(device_t dev, void *priv, bool raw)
{
struct max77620_softc * const sc = device_private(dev);
struct max77620_pin *gpin = priv;
uint8_t gpio;
int val;
I2C_LOCK(sc);
gpio = I2C_READ(sc, MAX_GPIO_REG(gpin->pin_num));
I2C_UNLOCK(sc);
val = __SHIFTOUT(gpio, MAX_GPIO_INPUT_VAL);
if (!raw && gpin->pin_actlo)
val = !val;
#ifdef MAX77620_DEBUG
device_printf(sc->sc_dev, "GPIO%d rd %02x (%d %d)\n",
gpin->pin_num, gpio,
(int)__SHIFTOUT(gpio, MAX_GPIO_INPUT_VAL), val);
#endif
return val;
}
static void
max77620_gpio_write(device_t dev, void *priv, int val, bool raw)
{
struct max77620_softc * const sc = device_private(dev);
struct max77620_pin *gpin = priv;
uint8_t gpio;
if (!raw && gpin->pin_actlo)
val = !val;
I2C_LOCK(sc);
gpio = I2C_READ(sc, MAX_GPIO_REG(gpin->pin_num));
gpio &= ~MAX_GPIO_OUTPUT_VAL;
gpio |= __SHIFTIN(val, MAX_GPIO_OUTPUT_VAL);
#ifdef MAX77620_DEBUG
device_printf(sc->sc_dev, "GPIO%d wr %02x -> %02x\n",
gpin->pin_num,
I2C_READ(sc, MAX_GPIO_REG(gpin->pin_num)), gpio);
#endif
I2C_WRITE(sc, MAX_GPIO_REG(gpin->pin_num), gpio);
I2C_UNLOCK(sc);
}
static struct fdtbus_gpio_controller_func max77620_gpio_funcs = {
.acquire = max77620_gpio_acquire,
.release = max77620_gpio_release,
.read = max77620_gpio_read,
.write = max77620_gpio_write,
};
static void
max77620_gpio_attach(struct max77620_softc *sc)
{
fdtbus_register_gpio_controller(sc->sc_dev, sc->sc_phandle,
&max77620_gpio_funcs);
}
static int
max77620_match(device_t parent, cfdata_t match, void *aux)
{
struct i2c_attach_args *ia = aux;
int match_result;
if (iic_use_direct_match(ia, match, compat_data, &match_result))
return match_result;
return 0;
}
static void
max77620_attach(device_t parent, device_t self, void *aux)
{
struct max77620_softc * const sc = device_private(self);
struct i2c_attach_args *ia = aux;
sc->sc_dev = self;
sc->sc_i2c = ia->ia_tag;
sc->sc_addr = ia->ia_addr;
sc->sc_phandle = ia->ia_cookie;
aprint_naive("\n");
aprint_normal(": MAX77620 Power Management IC\n");
max77620_gpio_attach(sc);
}
CFATTACH_DECL_NEW(max77620pmic, sizeof(struct max77620_softc),
max77620_match, max77620_attach, NULL, NULL);